A new study indicates that we will enter the post-PC era this year. On Tuesday, industry researcher NPD DisplaySearch predicted that global sales this year of tablets will, for the first time, exceed those of notebooks and cross over the 50 percent threshold in the mobile PC market.

In its Quarterly Mobile PC Shipment and Forecast Report, the company projects that 2013 will see more than 240 million tablets shipped worldwide, besting the estimated 207 million notebook PCs expected in the next 12 months. In 2012, tablet shipments exceeded notebooks in North America and China for the first time. NPD considers tablets and PCs to be in the same category, and, in fact, often describes tablets as "tablet PCs."

NPD noted that, although the tablet category has been dominated by Apple's iPad since its launch in 2010, opportunities for other players will drive shipment growth to a phenomenal 64 percent compared with 2012.

Screen Size Varieties

A key factor in those new opportunities, the report noted, is the new variety of screen sizes, notably tablets with sizes that are smaller than the 9.7 inches of the original iPad. In fact, the report sees tablets with 7 to 8 inches as accounting for 45 percent of the market this year, with the 9.7 inch size taking only about 17 percent market share.

Another driver of growth for tablets, as it has been for smartphones and notebook PCs, is increased sales in emerging markets. Key among these new markets is China, which NPD projects will have 27 percent of the global tablet market this year, with the greatest growth being from Chinese brands.

Tablets have quickly become more PC-like, with a range of applications for most brands and, for some, an easy ability to attach a keyboard. Microsoft's Windows-based Surface tablet, for instance, has promoted its cover-with-keyboard.

At the same time, NPD predicts that 2013 will see more tablet-like features coming to many notebook PCs, such as instant-on, all-day battery life and new form factors, including tablet-notebook hybrids that are just beginning to move into the market.

75 Percent by 2017

Richard Shim, senior analyst with NPD DisplaySearch, said in a statement that major brands increased investment for tablets in the North American market in the second half of 2012, testing various screen sizes and price points.

"The subsequent increase in shipments and demand underscored the benefits of segmentation in the market as it drove rapid market expansion," he noted, adding that further investment in 2013 will continue to fuel growth.

In fact, NPD sees tablets continuing a steady growth worldwide at least over the next five years, reaching nearly 75 percent of the total market of mobile PC products by 2017.

Laura DiDio, an analyst with Information Technology Intelligence Consulting, said that this rapid transition to the era of tablet dominance doesn't surprise her, ever since she got over her "initial shock at the millions of iPads" that were sold within the first six months of its release in April 2010.

She pointed out that the screen size diversity includes not only smaller-than-original-iPad sizes, but such variations as the new 27-inch Lenovo tablet unveiled this week at the Consumer Electronics Show in Las Vegas. It's intended to be used on a stand as well as flat on a table, DiDio said, adding that it was also large enough to become a Web-based TV screen on the wall.